Metal/PS/c-Si photodetectors based on unoxidized and oxidized porous silicon

Highly doped ZnO films deposited by spray-pyrolysis. Design parameters for optoelectronic applications

“…Devices with this configuration are usually rectifying due to the formation 435 of interface barriers. The associated carrier transport mechanisms are similar to those observed in a normal p-n heterojunction [53], showing a rectification ratio in darkness of approximately 400 at ±3 V. The rectification ratio for this J-V curve obtained in dark was approximately 100 at ±3 V. In the reverse bias region, an increase in the photogenerated current could be observed when illumination was applied. The current was [ Figure 10 about here] 445 The experimental data presented in Fig.…”

“…The current was [ Figure 10 about here] 445 The experimental data presented in Fig. 10(b) were fitted with a simple diode model [53]. As a result, we obtained the following set of parameters: series resistance (R s ), parallel resistance (R p ), reverse saturation current (I 0 ) and ideality factor (n).…”

Photodetectors based on porous silicon produced by Ag-assisted electroless etching

“…Indeed, the absorption in porous silicon is very low for wavelengths above 500 nm, thus, most of the light is absorbed in the p-Si substrate itself [21]. This is in accordance with the fact that the spectral sensibility spectrum of these structures is almost identical with those of silicon photodiodes which possess an important spectral sensitivity in the range 450-1100 nm with a peak around 850 nm [19][20][21].…”

“…It is established that photodiodes spectral sensitivity of the metal/PS/Si/metal structure, in the case where porous silicon is formed anodically, is determined by carrier photogenerated in the substrate near to the PS/c-Si heterojunction [20]. Indeed, the absorption in porous silicon is very low for wavelengths above 500 nm, thus, most of the light is absorbed in the p-Si substrate itself [21].…”

Transport of carriers in metal/porous silicon/c-Si device structures based on oxidized porous silicon

“…[2][3][4][5] Transport properties of oxidized metal/PS/p-Si structures have been investigated even less although relatively effective and stable electroluminescent device 6 and photodetector 7 structures based on oxidized PS were fabricated. In a recent article 7 we reported Al/PS/p-Si photodiode structures based on nonoxidized and oxidized PS including structures with a high porosity ͑up to 85%͒ of PS. In this article detailed transport properties of the same oxidized device structures are presented.…”